In the related art, in order to improve S/N, there is a known image processing apparatus generating a composite image by performing compositing of an input frame image and a preceding frame image in which noise is reduced (for example, refer to PTL 1).
PTL 1 discloses an image processing apparatus that uses a finite difference value (specifically, a finite difference value of luminance) between the input frame image and the preceding frame image in which noise is reduced. The image processing apparatus is determined to be moving in a case where the finite difference value between the frame images is greater than a threshold and is determined to be stationary in a case where the finite difference value therebetween is smaller than the threshold. Moreover, the image processing apparatus reduces an after-image of a mobile object by adjusting the value of a composite ratio of the preceding frame image subjected to compositing with the input frame image to a smaller value with respect to an image area in which motion is present, based on a determination result.